Quick-acting switch mechanism



I Dec. 3, 1946. R. H. BENTLEY QUICK-ACTING SWITCH MECHANISM Filed Nov. 9, 1943 ZI///// V /A fiveniar ROBERT H. BENTLEY 6y his attorney-s Patented Dec. 3, 1946 QUICK-ACTING SWITCH MECHANHSM Robert H. Bentley, Hartiord, @onn, assignor to The Arrow-Hart & Hegeman Electric (3cmpany, Hartford, Coma, a corporation of 6onnecticut Application November 9, 1943, Serial No. biitttiifii 4 illaims.

This invention relates to snap action electric switch mechanisms. More particularly, it relates to a mechanism suitable for multi-pole electric switches wherein it is desired to break simu1- taneously each of the multiple lines controlled by the switch.

It is an object of my invention to provide an improved electric switch mechanism particu= larly adapted for use in multi-pole electric switches of low alternating current ratings.

Another object of the invention is to providean improved switch mechanism which will cause simultaneous break in all the lines controlled by the switch and which may be economically constructed and-assembled.

Another object of the invention is to provide an economical structure for an electric switch of small size for use in multi-circuit arrangements, in which the breaks in all of the lines shall occur simultaneously and which will have a substantial interrupting capacity in comparison to its small size.

Other objects and advantages of my invention will become apparent as it is described in corn nection with the accompanying drawing.

In the drawing-- Fig. 1 is a longitudinal section view through the center of an electric switch mechanism embodying the invention;

Fig. 2 is a section view similar to Fig. 1, but with parts in closed-circuit position;

Fig. 3 is a transverse section view, the section being taken along line 3-3 of Fig. 2;

Figs. 4, 5 and 6 show, in exploded perspective, certain parts of the mechanism for operating the movable contact.

Referring to the drawing, the switch contacts and terminals are mounted within a rectangular molded insulating base 10 hollowed out for the reception of three identical sets of contacts located in parallel chambers l2, l4, 16, which are separated by longitudinally extending partitions- I3 and I 5 formed integral with the base.

Each of the contact sets comprises a pair of fixed stamped bar contacts 20, 22 secured upon ledges 24, 25 at opposite ends of the base by hollow internally-threaded rivets 28 which project through the bottom of the base to receive terminal screws 30. Each of the fixed contacts 20, 22 extends into a cavity such as He in the central part of each of compartments l2, l4 and I6, and has a conventional highly-conductive button-like contact tip facing downwardly into the cavity for engagement with similar contact tips on a movable bridging contact bar 38 which is normally spring-pressed upwardly into engagement with the fixed contacts by coiled compression spring at between the bridging contact and the bottom of the cavity.

In order to insulate the bridging contact from the mechanism for operating it to open circuit position, an insulating plunger member at, preferably made of molded insulating material, rests upon the top surface of each bridging contact and is guided in its movement by channels formed in the side walls oi the base and of the partitions l3 and is.

Because the several sets of fixed and movable contacts are individual units and ordinarily would not be dependent on one another for movement in unison, it has been found needful to provide actuating mechanism for causin simultaneous opening and closing movement of the contacts in order to avoid excessive arcing between the contact surfaces. To accomplish this object, I have provided a frame or contactmoving member made up of three similar parallel stamped sheet metal ribs 5b, and each having laterally-directed arms 56a, 52a, b ia at their ends. These arms are each provided with a pair of small neighboring apertures through which pass parallel pins 5t, 58, which are, or may be, soldered or otherwise amxed to the arms of the ribs 58, 52, 54% to form a rigid unit. Between the neighboring pins 55, 58 the ends of a leaf spring member 6b are inserted. This member 60 may be stamped from thin resilient sheet metal in the form indicated best in Fig. 6. To accommodate the arms 50a, 52a, 54a, slots 62 may be cut into the end edges of the leaf spring memher. It may thus be observed that the leafspring and the frame or contact-moving member I form a contact operating unit.

In order that an over-center action may be produced, the leaf spring member has an H-shaped slot 64 stamped in its central portion providing two short arms 88 whose ends engage in a circumferential groove formed near the end of an actuator in the form of an operating pin or plunger member 10. To bow the arms 66 and give the leaf spring a bias, the diameter or thickness of the portion or the plunger 10 engaged by the arms 68 is greater than the distance between the ends of the arms 66 in their normal flat aligned state.

At the central portions. of the ribs 50, 52 and M, cylindrical studs 50s, 52s, 54s are afllxed. The studs 50s and 54s extend laterally inwardly from one side of the ribs 50 and 54, and the stud I23 extends from both sides 01 the rib 52. These 3 studs are aligned and are adapted to seat within the insulating plungers 42 so that upon movement of the frame, the plungers will be caused to simultaneously move downwardly to cause the bridging contacts to disengage the fixed contacts simultaneously.

To guide rectilinear movement of the plunger Ill, a diametrical slot 12 is cut into the inner end of the plunger to receive short guide pins 14 radially extending inward from the walls of a central aperture I6 formed in a rectangular cover member 18 for the base I0. The cover member 18 mayconveniently be made of molded insulating material and hollowed out on its inner surface. for the reception ofthe operating mecna nism.

Normally urging the plunger outward of the cover 18 is a compression spring 82 coiled around the'plunger. One end of this spring 82 presses against the under side of a flange H formed on the upper and outer end of the plunger 10; the

opposite end of the spring presses upon the floor of a circular recess 84 in the cover concentric with the plunger-receiving recess I6. The recess 84 preferably will be the same diameter as the inner fianged end of I an insulating button 80 that covers and insulates the outer end of the plunger it. The flanged end of the button Bll may be secured in the recess 84 by a stamped sheet metal bridge member 86; and the bridge moving member acting upon said bridging contacts to move them simultaneously, a'leaf spring member having an H-shaped aperture providing resilient portions for providing a bias of said spring member into one or another of two conditions, said leaf spring member engaging at its ends with said contact-moving member, and an operating pin engaged by said resilient portions for changing the direction of bias of said leaf spring member.

2. In an electric switch, a casing, a plurality of fixed and movable contacts therein, a'contactmoving member acting upon said movable contacts to move them simultaneously, a leaf spring member cooperating at itsends with said contact-moving member and having positions of opposite bias for locating said contact-moving member in spaced positions, means in the bottom member 86 may be secured to the cover by ment with the stationary contacts 22, 2Q.

' Release of the button 80 will permit the re-' turn spring 82 to reverse the condition of spring arm 66, forcing the frame down and overcoming the lesser force of contact springs 50 to move the bridging contacts to open position.

Many modifications within the scope of the invention will occur to those skilled in the art. Therefore I do not limit the invention to the embodiment disclosed.

I claim:

1. In an electric switch, a plurality of independent sets of fixed and movable contacts each comprising a pair of fixed contacts and a bridging contact, spring means biasing said bridging contact into closed circuit position, in combination with actuating means comprising a contactof said casing supporting said contact-moving member during change of bias in.one direction. means in the top of said casing supporting said contact-moving member during'change of bias in the other direction, and a manually operable actuator for changing said bias. I

3. In an electric switch, a casing, a plurality of fixed and movable contacts therein, said movable contacts being independently movable, a contact-moving member acting upon said movable contacts to move them simultaneously, a leaf spring member cooperating at its ends with said contact-moving member and having positions of opposite bias for locating said contactmoving member in spaced positions, means in the bottom of said casing supporting said contactmoving member during change of bias in one direction, means in the top of said casing supporting said contact-moving member during change of bias in the other direction, and an actuator manually operable in one direction to with said contact-moving membenan actuator engaged by stressed portions of said leaf spring member to provide bias in opposite directions forlocating said unit in different positions, means in the bottom of said casing supporting said contact-moving member during change of bias in one direction, and means in the top of said casing supporting said contact-moving member during change of bias in the other direction.

ROBERT H. BENTLEY. 

